An Intranet is (66) the application of Internet technology within an internal or closed user group. Intranets are company (67) and do not have a (68) connection to the Internet. Used properly an Intranet is highly effective corporate tool, capable of regularly (69) information to empower the workforce with the information needed to perform their roles. Used in this way, an Intranet represents a step towards the (70) office.
（69）是（）
A.update
B.updated
C.updates
D.updating